Elevator cars typically move vertically up and down in a hoistway. The hoistway is usually a closed space inaccessible to others but maintenance persons. Such situation may arise where a maintenance person needs to get access to elevator components positioned in the hoistway. This type of situation may arise for example when maintenance work, inspection work or installation work needs to be done to the elevator components positioned in the hoistway. The maintenance person can enter the hoistway for example via a door between landing and the hoistway when the car is not blocking the way behind the door opening. Sometimes, to carry out the work it is necessary to stand between the elevator car and the end of the hoistway in the pit floor or on the roof of the elevator car. This poses a threat of being hurt if the car unintentionally moves too far towards the end of the hoistway. These situations can be dangerous, especially if the car can be driven during normal elevator use very close to the end of the hoistway. In prior art, these situations are made safer by activatable safety arrangements, which can stop the car from traveling too close to the end of the hoistway. Such solutions are known, for example, where the car brake can be set to be automatically triggered when the car reaches a predetermined position in the hoistway. In this way, a safety space can be temporarily formed in the end of the hoistway. The elevator car is thus prevented from proceeding into this temporary safety space. Solutions of this type have the problem that the car may be already driven past said predetermined position, when a person activates the system and enters the hoistway. Thus, a person entering the hoistway might be in danger even though he has activated the system for restricting car from moving to its extreme position. Also, it may be unclear for the maintenance person whether it's safe to enter the hoistway or not. Especially in systems where the activation is carried out remotely it may be unclear whether the safety system is reliably activated or not. This problem could be overcome by setting said predetermined position so close to the end of the hoistway that the person entering the hoistway can visually verify that the car is above said predetermined position and that the safety system is correctly activated. However, this necessitates relying on visual observation, which may be difficult of even forgotten. Thus, this alternative is not totally free of risk. Also, if said predetermined position is set close to the hoistway end, the safety space may become too low, because after passing said predetermined position of triggering the brake the car still continues a certain unpredictable braking distance until the car brake is fully stopped. Accordingly, also setting said predetermined position close to the end of the hoistway has drawbacks. Known solutions for providing a temporary safety space are disclosed for example in publications US2008099284A1, EP1118574A2 and U.S. Pat. No. 5,727,657A.
It is common in elevators to form a safety space in upper and lower end of the elevator in the same way. In these cases, the devices meant to work at upper end of the hoistway work otherwise similarly as the devices at the lower end, but they are arranged to work oppositely in the vertical sense. Also in the above described elevators having a predetermined position for triggering the car brake (i.e. elevators with pretriggering safety devices) a safety space can be formed in the upper and lower end of the hoistway in the same way.